template.spec.js

describe( 'Top level suite', function() {

    describe( 'Second level test suite', function() {

        before( function() {
            // executes once, before all tests 
        } );

        beforeEach( function() {
            // executes before each test of the suite
        } );

        after( function() {
            // executes once, after all tests
        } );

        afterEach( function() {
            // executes after each test of the suite
        } );

        it( 'should verify a behavior', function() {
            // a test containing assertions
        } );
        
        it('should verify an async behaviour', function() {
            setTimeout(() => {
              try {
                // expect here
                done()
              } catch(e) {
                done(e)
              }
            }, 100)
        })

        xit( 'should be a pending test', function() {
            // this test is pending. All assertions inside are ignored.
        } );    

        it.skip( 'should also be a pending test', function() {
            // it.skip is a longer, more semantic form of xit
        } );        

        it( 'should also be a pending test' );
    } );

    describe( 'Another second level test suite', function() {

    } );
} );

describe( 'Maintainable unit test cases...', function( ) {
    it( 'should test one type of behavior' );
    it( 'should not depend on any other test cases.' );
    it( 'should execute with exact same initial state as any other tests in the suite.' );
    it( 'should not matter in which order are these tests executed.' );
} );